Frequency shift interference type light vector analysis device

Abstract

The invention provides a frequency shift interference type light vector analysis device, which belongs to the technical field of optical testing and comprises a tunable laser source, an auxiliary interferometer module, a frequency shift orthogonal polarization generation module, a frequency shift interference testing module, a polarization diversity detection module and a to-be-tested device information acquisition module. The method is characterized in that frequency shifters are introduced into reference arms of the frequency shift orthogonal polarization generation module and the frequency shift interference test module to regulate and control the frequency shift amount, so that the frequency resolution performance of optical vector analysis is improved. The frequency shifter is adopted to replace an extended optical fiber to improve the equivalent arm length difference of the interferometer, so that the phase noise problem caused by the extended optical fiber is reduced, and the frequency resolution of the device can be greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of optical testing, and in particular relates to a frequency-shift interferometry optical vector analysis device. Background Art

[0002] Spectral response characteristics are important parameters for the development and manufacture of optical devices, optical systems, and photonic integrated circuits. In the process of device preparation, production, and application, it is essential to test the spectral response of the device. Optical vector analyzer (OVA) based on swept light source and optical interferometer is widely used to test the loss, delay, and polarization-related characteristics of optical devices. Due to the wide wavelength scanning range of the tunable laser, the test range can completely cover the C+L band, and the test speed reaches seconds (Apparatus and method for the complete characterization of optical devices including loss, birefringence and dispersion effects, US7042573B2), but its frequency resolution is only 200MHz, which is difficult to meet the development needs of today's high-precision devices.

[0003] Since optical devices have polarization characteristics, orthogonal polarization inquiry light is injected into the device to obtain information about the device in two different polarization directions, and the polarization characteristics of the device are obtained. Polarization error is the main error based on the swept light source and optical interferometer OVA. In 2023, Yu Zhangjun and others from Guangdong University of Technology proposed an online polarization alignment method (an optical vector analysis device and method for online polarization alignment, CN116222979A), which effectively suppresses the error caused by polarization adjustment; in the same year, the same research group also proposed a polarization-maintaining fiber solution (a polarization-free optical vector analysis device based on a cascaded polarization-maintaining interferometer, application number: 202310422850.X), which effectively suppresses polarization errors by utilizing the characteristics of polarization-maintaining devices and the polarization stability of polarization-maintaining fibers.

[0004] Since there is a certain time delay between the two polarization states of the interrogation light, they are also separated in time in the detection signal and can be distinguished. This is why this method needs to introduce a certain time delay between the two orthogonal polarization interrogation lights. The device consists of two interferometer cascades, and the two interferometer cascades produce four interference signal peaks. The positions of the four interference peaks are related to the frequency difference of the two interferometers. The frequency difference of the first interferometer will affect the effective resolution of the device, and the frequency difference of the second interferometer will change due to the length of the device under test.

[0005] The present invention provides a frequency-shifting interferometer optical vector analyzer, which adjusts the frequency difference between the two arms of two interferometer modules through a frequency shifter. The frequency difference of the first interferometer determines the effective frequency resolution of the device, which can increase the effective resolution of the device to a certain extent. Since the positions of the four interference peaks need to be distinguished, the frequency difference between the two arms of the second interferometer module with the device to be measured must be greater than three times that of the first interferometer. Since it is troublesome to replace the extended optical fiber, and the long optical fiber will introduce phase noise, and the frequency shifter directly raises the overall frequency, there is no phase noise caused by the optical fiber. The present invention uses a frequency shifter instead of an extended optical fiber to increase the equivalent arm length difference of the interferometer, reduce the phase noise problem caused by the extended optical fiber, and greatly improve the frequency resolution of the scheme. Summary of the invention

[0006] The purpose of the present invention is to provide an optical vector analysis device with short test time and simple structure. A frequency-shift interferometer optical vector analysis device, comprising a tunable laser source 101, an auxiliary interferometer module 1, a frequency-shift orthogonal polarization generation module 2, a frequency-shift interferometer test module 4, a polarization diversity detection module 5 and a device-to-be-tested information acquisition module 6, characterized in that:

[0007] The tunable laser source 101 generates a linear frequency-sweeping continuous light whose wavelength changes with time at a rate γ, which is split by the first coupler 102, one beam is injected into the auxiliary interferometer module 1, and the other beam is injected into the frequency-shifted orthogonal polarization generation module 2;

[0008] The frequency-shifted orthogonal polarization generating module 2 comprises a second coupler 201, a first frequency shifter 205, a first driver 204, a first polarization controller 202, a third coupler 203 and a first detector 206, wherein the linear frequency-sweeping continuous light is injected into the second coupler 201 and divided into two beams, one beam is injected into the first frequency shifter 205 after passing through the second output end 201b of the second coupler, and the output light is then injected into the second input end 203b of the third coupler, and the other beam is injected into the first output end 201a of the second coupler with the polarization controller 202, and injected into the first input end 203a of the third coupler after passing through the first polarization controller 202. The two beams output by the second coupler 201 are split after being combined in the third coupler 203, one beam enters the first detector 206 for detecting the working state of the frequency-shifted orthogonal polarization generating module 2, and the other beam is injected into the frequency-shifted interference testing module 4 after passing through the second polarization controller 301, and the time delay difference between the upper and lower arms of the frequency-shifted orthogonal polarization generating module 2 is τ;

[0009] The frequency-shifting interference test module 4 includes a fourth coupler 401, a second frequency shifter 405, a second driver 404, a device under test 402 and a fifth coupler 403. The output light of the frequency-shifting orthogonal polarization generating module 2 passes through the second polarization controller 301, and then passes through the fourth coupler 401 to be divided into two beams. One beam is input from the first output end 401a of the fourth coupler to the first input end 403a of the fifth coupler after passing through the device under test 402, and the other beam is injected into the second frequency shifter 405 after passing through the second output end 401b of the fourth coupler. The output light is then injected into the second input end 403b of the fifth coupler. The two beams are combined in the fifth coupler 403 and input into the polarization diversity detection module 5. The time delay difference between the upper and lower arms of the frequency-shifting interference test module 4 is τ D ;

[0010] The polarization diversity detector module 5 includes a polarization beam splitter 501, a p detector 502, and an s detector 503, wherein the polarization beam splitter 501 splits the output light of the frequency shift interference test module 4 into two beams according to the polarization state and injects them into the p detector 502 and the s detector 503 respectively, and injects the interference fringe signal into the device under test information acquisition module 6 after photoelectric conversion to obtain the transmission characteristics of the device;

[0011] The device under test information acquisition module 6 includes an interference fringe acquisition module 601, a feature filter extraction module 602, a transfer function acquisition module 603, and a transmission characteristic acquisition module 604. The interference fringe signals from the p detector 502 and the s detector 503 are converted into digital signals p-polarized interference fringes 601a and s-polarized interference fringes 601b respectively after analog-to-digital conversion in the interference fringe acquisition module 601. They are then processed in the feature filter extraction module 602 and enter the transfer function acquisition module 603, and then the transfer function of the device under test is obtained. Finally, the light vector transmission characteristics such as amplitude, phase, and polarization of the device under test are extracted in the transmission characteristic acquisition module 604.

[0012] The auxiliary interferometer module 1 includes a sixth coupler 103, a delay optical fiber 104, a seventh coupler 105, and a balanced detector 106. The sixth coupler 103 divides the light from the first coupler 102 into two beams, one beam is injected into the first output end 103a of the sixth coupler, and the other beam is injected into the delay optical fiber 104 via the second output end 103b of the sixth coupler. The two beams are combined in the seventh coupler 105 and then divided into two beams, and then injected into the balanced detector 106 for differential detection. The interference fringe signal after photoelectric conversion is injected into the interference fringe acquisition module 601, where it is square-wave shaped and used as a sampling trigger signal;

[0013] The first driver 204 provides a frequency shift amount of Ω1 for the first frequency shifter 205, and adjusts the frequency difference ΔΩ1=γτ+Ω1 between the two arms of the frequency shift orthogonal polarization generating module 2, so that the frequency shift orthogonal polarization generating module 2 outputs a pair of orthogonal polarization inquiry lights with a certain frequency difference. The second driver 404 provides a frequency shift amount of Ω2 for the second frequency shifter 405, and adjusts the frequency difference ΔΩ2=γτ between the two arms of the frequency shift interference testing module 4. D +Ω2.

[0014] The frequency-shift interferometry optical vector analysis device according to claim 1 is characterized in that:

[0015] The frequency difference ΔΩ1 between the two arms of the frequency-shift orthogonal polarization generating module 2 and the frequency difference ΔΩ2 between the two arms of the frequency-shift interference testing module 4 satisfy: ΔΩ2≥3ΔΩ1.

[0016] The frequency-shift interferometry optical vector analysis device according to claim 1 is characterized in that:

[0017] In the frequency-shifted orthogonal polarization generating module 2, the first polarization controller 202 is adjusted to rotate the polarization direction of the transmitted light. The first detector 206 is used to monitor the working state of the frequency-shifted orthogonal polarization generating module 2. When the amplitude of the interference fringe signal of the first detector 206 is the minimum, the adjustment of the first polarization controller 202 is stopped.

[0018] The frequency-shift interferometry optical vector analysis device according to claim 1 is characterized in that:

[0019] When the device under test 402 is not connected, the second polarization controller 301 is adjusted, and the adjustment of the second polarization controller 301 is stopped when the difference between the signal amplitude output by the p detector 502 and the signal amplitude output by the s detector 503 is the smallest.

[0020] The frequency-shift interferometry optical vector analysis device according to claim 1 is characterized in that:

[0021] The p-polarized interference fringes 601a and the s-polarized interference fringes 601b output by the interference fringes acquisition module 601 can establish a functional relationship with the angular frequency of the linear frequency sweeping light, which are I p (ω) and I s (ω), in the feature filter extraction module 602, the p-polarized interference fringe 601a passes through the first unilateral digital bandpass filter 6021 to obtain a first complex signal 602a, denoted as h 11 (ω), the p-polarized interference fringe 601a passes through the second unilateral digital bandpass filter 6022 to obtain a second complex signal 602b, denoted as h 12 (ω), the s-polarized interference fringe 601b passes through the first unilateral digital bandpass filter 6021 to obtain a third complex signal 602c, denoted as h21 (ω), the s-polarized interference fringe 601b passes through the second unilateral digital bandpass filter 6021 to obtain a fourth complex signal 602d, denoted as h 22 (ω), and then the device transfer matrix 603a is formed in the transfer function acquisition module 603, which is recorded as H(ω)=[h ij (ω)] 2×2 Finally, the amplitude transmission characteristic, phase transmission characteristic, and polarization transmission characteristic of the device are calculated in the transmission characteristic acquisition module 604, specifically,

[0022] The amplitude transfer characteristic of the device, i.e., insertion loss, can be calculated as:

[0023]

[0024] The phase transfer characteristic, i.e. group delay, can be calculated as:

[0025]

[0026] In the polarization transmission characteristics, the polarization-dependent loss can be calculated as:

[0027] Among them, T max and T min is the eigenvalue of the matrix obtained by multiplying H(ω) with its conjugate transposed matrix;

[0028] In the polarization transmission characteristics, polarization mode dispersion can be calculated as:

[0029]

[0030] Among them, ρ1 and ρ2 are H(ω+Δω)H(ω) -1 The characteristic value of .

[0031] According to the frequency-shifting interferometry optical vector analysis device described in claim 1, it is characterized in that: the center frequency of the first unilateral digital bandpass filter 6021 is ΔΩ2-ΔΩ1, and the bandwidth is ΔΩ1; the center frequency of the second unilateral digital bandpass filter 6022 is ΔΩ2+ΔΩ1, and the bandwidth is ΔΩ1.

[0032] The advantages of the present invention are as follows: the present invention is a light vector characteristic testing device based on frequency shifting interference, which uses a frequency shifter to control the frequency difference between two interferometer modules, thereby reducing the influence of polarization instability and phase noise introduced by long optical fibers; and uses a frequency shifter to match the frequency difference between the two interferometers, thereby increasing the equivalent arm length difference of the interferometers, thereby greatly increasing the wavelength resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of a frequency-shift interferometry optical vector analysis device.

[0034] Attached Figure 1 In: 1—auxiliary interferometer module; 2—frequency shift orthogonal polarization generation module; 4—frequency shift interference test module; 5—polarization diversity detection module; 6—device under test information acquisition module; 101—tunable laser source; 102—first coupler; 103—sixth coupler; 103a—first output end of the sixth coupler; 103b—second output end of the sixth coupler; 104—delay fiber; 105—seventh coupler; 106—balanced detector; 201—second coupler; 201a—first output end of the second coupler; 201b—second output end of the second coupler; 202—first polarization controller; 203—third coupler; 203a—first input end of the third coupler; 203b—second input end of the third coupler; 204— The first driver; 205—the first frequency shifter; 206—the first detector; 301—the second polarization controller; 401—the fourth coupler; 401a—the first output terminal of the fourth coupler; 401b—the second output terminal of the fourth coupler; 402—the device to be tested; 403—the fifth coupler; 403a—the first input terminal of the fifth coupler; 403b—the second input terminal of the fifth coupler; 404—driver 2; 405—frequency shifter 2; 501—polarization beam splitter; 502p—detector; 503s—detector; 601—interference fringe acquisition module; 601a—p polarization interference fringe; 601b—s polarization interference fringe; 602—feature filtering extraction module; 603—transmission function acquisition module; 604—transmission characteristic acquisition module.

[0035] Figure 2 is the frequency domain image of p detector and s detector

[0036] Attached Figure 2 Middle: A—the frequency difference ΔΩ1 corresponding to the peak of the frequency shifting orthogonal polarization generating module 2; B—the frequency difference ΔΩ2-ΔΩ1 corresponding to the peak of the frequency shifting interference test module 4 and the frequency shifting orthogonal polarization generating module 2; C—the frequency difference ΔΩ2 corresponding to the peak of the frequency shifting interference test module 4; D—the sum of the frequency differences ΔΩ2+ΔΩ1 corresponding to the peak of the frequency shifting interference test module 4 and the frequency shifting orthogonal polarization generating module 2; 6021 unilateral digital bandpass filter; 6022 unilateral digital bandpass filter. DETAILED DESCRIPTION

[0037] In order to clearly illustrate the optical vector analysis device of the present invention, the present invention is further described in conjunction with the embodiments and drawings, but this should not limit the protection scope of the present invention.

[0038] The main optoelectronic device selection and its parameters are as follows:

[0039] 1) The tunable laser source 101 is a TSL-770 laser from Santec. When testing the device, the wavelength tuning range is 1510nm to 1590nm, and the sweep rate is 80nm / s;

[0040] 2) The acquisition card model is M4i:4471-x8, the sampling rate is 200MHz / s, and the maximum acquisition voltage is 2.5V;

[0041] 3) The splitting ratio of the first coupler 102 is 99:1, wherein 99% of the light is input to the frequency-shifted orthogonal polarization generating module 2, and 1% of the light is input to the auxiliary interferometer module 1; the splitting ratios of the second coupler 201, the third coupler 203, the fourth coupler 401, the fifth coupler 403, the sixth coupler 103 and the seventh coupler 105 are all 50:50, the insertion loss is less than 0.5dB, the operating wavelength is 1550±40nm, and the pigtail length is 1m;

[0042] 4) The first polarization controller 202 and the second polarization controller 301 are three-ring polarization controllers with a length of 2 m;

[0043] 5) The first frequency shifter 205 is of model SGTF20-1550-1P, with an operating frequency of 20 MHz, and the second frequency shifter 405 is of model SGTF80-1550-1P; the first driver 204 and the second driver 404 are both low-power N-type acousto-optic drivers, the first driver is of model SGY20-33-N-1D, with an operating frequency of 20 MHz, and the second driver is of model SGY80-33-N-1D, with an operating frequency of 80 MHz;

[0044] The device under test is a dense wavelength division multiplexer (DWDM) with a test port operating center wavelength of 1550nm, a length of 10m, and a refractive index of 1.456.

[0045] A frequency-shift interferometry optical vector analysis device, the test method is as follows:

[0046] The tunable laser source 101 generates a linear frequency-sweeping continuous light whose frequency varies with time γ, which is split by the first coupler 102, one beam is injected into the auxiliary interferometer module 1, and the other beam is injected into the frequency-shifted orthogonal polarization generation module 2;

[0047] A beam of linear frequency-sweeping continuous light injected into the frequency-shifted orthogonal polarization generating module 2 is injected into the second coupler and then divided into two beams. One beam is injected into the first frequency shifter 205 after passing through the second output end 201b of the second coupler, and outputs light with a frequency shift of 20MHz compared to the input light, and then is injected into the second input end 203b of the third coupler; the other beam is injected into the first output end 201a of the second coupler with the first polarization controller 202, passes through the first polarization controller 202, and then is injected into the first input end 203a of the third coupler. The two beams of light output by the second coupler 201 are combined in the third coupler 203 and then split. One beam enters the first detector 206 to monitor the working status of the frequency-shifted orthogonal polarization module 2, and the other beam is injected into the frequency-shifted interference test module 4 through the second polarization controller 301. The time delay difference between the upper and lower arms of the frequency-shifted orthogonal polarization generating module 2 is τ, thereby obtaining the frequency difference between the upper and lower arms of the frequency-shifted orthogonal polarization generating module ΔΩ1=Ω1+γτ=20.097MHz (in this example, Ω1 is 20MHz and γ is 80nm / s).

[0048] At this time, the device under test 402 is not connected, and the first polarization controller 202 is adjusted to rotate the polarization direction of the transmitted light. When the amplitude of the interference fringe signal of the first detector 206 is the smallest, the adjustment of the first polarization controller is stopped. At this time, it can be determined that the frequency-shifted orthogonal polarization generation module outputs a pair of frequency-shifted orthogonal polarized lights. Then, the second polarization controller 301 is adjusted. When the difference between the output signal amplitude of the p detector 502 and the signal amplitude output of the s detector 503 is the smallest, the adjustment of the second polarization controller is stopped, and then the device under test 402 can be connected.

[0049] The output light of the frequency-shifted orthogonal polarization generating module 2 is injected into the fourth coupler 401 of the frequency-shifted interference test module 4 after passing through the second polarization controller 301 and then divided into two beams. One beam is input from the first output end 401a of the fourth coupler to the first input end 403a of the fifth coupler after passing through the device under test 402. The other beam is injected into the second frequency shifter 405 after passing through the second output end 401b of the fourth coupler, and the output light has a frequency shift of 80MHz compared with the input light, and then injected into the second input end 403b of the fifth coupler. The two beams are combined in the fifth coupler 403 and input into the polarization diversity detection module 5. The time delay difference between the upper and lower arms of the frequency-shifted interference test module 4 is τ D , from which we can get the frequency difference between the upper and lower arms of the frequency shift interferometer test module 4 is ΔΩ2=Ω2+γτ D =80.485MHz (in this example, Ω2 is 80MHz and γ is 80nm / s).

[0050] Delay τ and τ D The calculation formula is Among them, L is the difference in length between the two arms, n is the refractive index, and c is the speed of light in a vacuum.

[0051] A digital bandpass filter is designed according to the frequency difference between the frequency-shifting orthogonal polarization generating module 2 and the frequency-shifting interference testing module 4, wherein the center frequency of the first unilateral digital bandpass filter 6021 is ΔΩ2-ΔΩ1, and the bandwidth is ΔΩ1; the center frequency of the second unilateral digital bandpass filter 6022 is ΔΩ2+ΔΩ1, and the bandwidth is ΔΩ1.

[0052] The polarization beam splitter 501 of the polarization diversity detector module 5 splits the output light of the frequency shift interference test module 4 into two beams according to the polarization state and injects them into the p detector 502 and the s detector 503 respectively. After photoelectric conversion, the interference fringe signal is injected into the device under test information acquisition module 6 to obtain the transmission characteristics of the device.

[0053] Another beam of linear frequency-sweep continuous light from the first coupler 102 is injected into the sixth coupler 103 of the auxiliary interferometer module 1 and then divided into two beams, one beam is injected into the first output end 103a of the sixth coupler, and the other beam is injected into the delay optical fiber 104 via the second output end 103b of the sixth coupler. The two beams are combined in the seventh coupler 105 and then divided into two beams, and then injected into the balanced detector 106 for differential detection. The interference fringe signal after photoelectric conversion is injected into the interference fringe acquisition module 601, where it is used as a sampling trigger signal after square wave shaping.

[0054] The p-polarized interference fringes 601a and the s-polarized interference fringes 601b output by the interference fringes acquisition module 601 can establish a functional relationship with the angular frequency of the linear frequency sweeping light, which are I p (ω) and I s (ω), in the feature filter extraction module 602, the p-polarized interference fringe 601a passes through the first unilateral digital bandpass filter 6021 to obtain a first complex signal 602a, denoted as h 11 (ω), the p-polarized interference fringe 601a passes through the second unilateral digital bandpass filter 6022 to obtain a second complex signal 602b, denoted as h 12 (ω), the s-polarized interference fringe 601b passes through the first unilateral digital bandpass filter 6021 to obtain a third complex signal 602c, denoted as h 21 (ω), the s-polarized interference fringe 601b passes through the second unilateral digital bandpass filter 6021 to obtain a fourth complex signal 602d, denoted as h 22 (ω), and then the device transfer matrix 603a is formed in the transfer function acquisition module 603, which is recorded as H(ω)=[h ij (ω)] 2×2 Finally, in the transmission characteristic acquisition module 604, according to equations (1) to (4), the amplitude transmission characteristic, phase transmission characteristic, and polarization transmission characteristic of the device can be calculated.

Claims

1. A frequency-shift interferometry optical vector analysis device, comprising a tunable laser source (101), an auxiliary interferometer module (1), a frequency-shift orthogonal polarization generation module (2), a frequency-shift interferometry test module (4), a polarization diversity detection module (5) and a device-to-be-tested information acquisition module (6), wherein: The tunable laser source (101) generates a linear frequency-sweeping continuous light whose frequency changes with time at a rate γ, which is split by a first coupler (102), one beam is injected into the auxiliary interferometer module (1), and the other beam is injected into the frequency-shifted orthogonal polarization generation module (2); The frequency-shifted orthogonal polarization generation module (2) comprises a second coupler (201), a first frequency shifter (205), a first driver (204), a first polarization controller (202), a third coupler (203) and a first detector (206), wherein linear frequency-sweep continuous light is injected into the second coupler (201) and is divided into two beams, one beam is injected into the first frequency shifter (205) after passing through the second output end (201b) of the second coupler, and the output light is then injected into the second input end (203b) of the third coupler, and the other beam is injected into the first polarization controller (202). 02), and then injected into the first input end (203a) of the third coupler after passing through the first polarization controller (202); the two beams of light output by the second coupler (201) are combined in the third coupler (203) and then split; one of the beams enters the first detector (206) for monitoring the working state of the frequency-shifted orthogonal polarization generating module (2); and the other beam passes through the second polarization controller (301) and is injected into the frequency-shifted interference testing module (4); the time delay difference between the upper and lower arms of the frequency-shifted orthogonal polarization generating module (2) is τ; The frequency-shift interference test module (4) comprises a fourth coupler (401), a second frequency shifter (405), a second driver (404), a device to be tested (402) and a fifth coupler (403). The output light of the frequency-shift orthogonal polarization generation module (2) passes through a second polarization controller (301) and then passes through a fourth coupler (401) to be divided into two beams. One beam is input from a first output end (401a) of the fourth coupler, passes through the device to be tested (402) and then inputs into a first input end (403a) of a fifth coupler. The other beam is injected into the second frequency shifter (405) after passing through a second output end (401b) of the fourth coupler. The output light is then injected into a second input end (403b) of the fifth coupler. The two beams are combined in the fifth coupler (403) and then input into a polarization diversity detection module (5). The time delay difference between the upper and lower arms of the frequency-shift interference test module (4) is τ. D ; The polarization diversity detection module (5) comprises a polarization beam splitter (501), a p detector (502), and an s detector (503), wherein the polarization beam splitter (501) splits the output light of the frequency shift interference test module (4) into two beams according to the polarization state and injects the two beams into the p detector (502) and the s detector (503) respectively, and injects the interference fringe signal into the device under test information acquisition module (6) after photoelectric conversion to obtain the transmission characteristics of the device; The device under test information acquisition module (6) comprises an interference fringe acquisition module (601), a characteristic filter extraction module (602), a transfer function acquisition module (603), and a transmission characteristic acquisition module (604). The interference fringe signals from the p detector (502) and the s detector (503) are converted into digital signals p polarization interference fringes (601a) and s polarization interference fringes (601b) respectively after analog-to-digital conversion in the interference fringe acquisition module (601). The signals are then processed in the characteristic filter extraction module (602) and enter the transfer function acquisition module (603), and then the transfer function of the device under test is obtained. Finally, the light vector transmission characteristics such as amplitude, phase, polarization, etc. of the device under test are extracted in the transmission characteristic acquisition module (604). The auxiliary interferometer module (1) comprises a sixth coupler (103), a delay optical fiber (104), a seventh coupler (105), and a balanced detector (106). The sixth coupler (103) divides the light from the first coupler (102) into two beams, one beam is injected into the first output end (103a) of the sixth coupler, and the other beam is injected into the delay optical fiber (104) via the second output end (103b) of the sixth coupler. The two beams are combined in the seventh coupler (105) and then divided into two beams. The two beams are then injected into the balanced detector (106) for differential detection. The interference fringe signal after photoelectric conversion is injected into the interference fringe acquisition module (601), where it is square-wave shaped and used as a sampling trigger signal. The first driver (204) provides a frequency shift amount of Ω1 for the first frequency shifter (205), and regulates the frequency difference ΔΩ1 = γτ + Ω1 between the two arms of the frequency shift orthogonal polarization generation module (2), so that the frequency shift orthogonal polarization generation module (2) outputs a pair of orthogonal polarization inquiry lights with a certain frequency difference. The second driver (404) provides a frequency shift amount of Ω2 for the second frequency shifter (405), and regulates the frequency difference ΔΩ2 = γτ between the two arms of the frequency shift interference test module (4). D + Ω2.

2. The frequency-shift interferometry optical vector analysis device according to claim 1, characterized in that: The frequency difference ΔΩ1 between the two arms of the frequency-shift orthogonal polarization generation module (2) and the frequency difference ΔΩ2 between the two arms of the frequency-shift interference test module (4) satisfy: ΔΩ2≥3ΔΩ1.

3. The frequency-shift interferometry optical vector analysis device according to claim 1, characterized in that: exist In the frequency-shift orthogonal polarization generation module (2), the first polarization controller (202) is adjusted to rotate the polarization direction of the transmitted light, and the first detector (206) is used to monitor the working state of the frequency-shift orthogonal polarization generation module 2. When the amplitude of the interference fringe signal of the first detector (206) is minimum, the adjustment of the first polarization controller (202) is stopped.

4. The frequency-shift interferometry optical vector analysis device according to claim 1, characterized in that: When the device under test (402) is not connected, the second polarization controller (301) is adjusted, and the adjustment of the second polarization controller (301) is stopped when the difference between the signal amplitude output by the p detector (502) and the signal amplitude output by the s detector (503) is minimal.

5. The frequency-shift interferometry optical vector analysis device according to claim 1, characterized in that: The p-polarized interference fringes (601a) and the s-polarized interference fringes (601b) output by the interference fringes collection module (601) can establish functional relationships with the angular frequency of the linear frequency sweeping light, which are I p (ω) and I s (ω), in the feature filter extraction module (602), the p-polarized interference fringes (601a) pass through the first unilateral digital bandpass filter (6021) to obtain a first complex signal (602a), denoted as h 11 (ω), the p-polarized interference fringes (601a) pass through the second unilateral digital bandpass filter (6022) to obtain a second complex signal (602b), denoted as h 12 (ω), the s-polarized interference fringes (601b) pass through the first unilateral digital bandpass filter (6021) to obtain a third complex signal (602c), denoted as h 21 (ω), the s-polarized interference fringes (601b) pass through the second unilateral digital bandpass filter (6021) to obtain a fourth complex signal (602d), denoted as h 22 (ω), and then the device transfer matrix (603a) is formed in the transfer function acquisition module (603), which is recorded as H(ω)=[h ij (ω)] 2×2 Finally, the amplitude transmission characteristic, phase transmission characteristic, and polarization transmission characteristic of the device are calculated in the transmission characteristic acquisition module (604), specifically, The amplitude transfer characteristic of the device, i.e., insertion loss, can be calculated as: The phase transfer characteristic, i.e. group delay, can be calculated as: GD ( ω ) = arg [ ∑ h ij ( ω ) h ij * ( ω − Δ ω ) ] Δ ω In the polarization transmission characteristics, the polarization-dependent loss can be calculated as: Among them, T max and T min is the eigenvalue of the matrix obtained by multiplying H(ω) with its conjugate transposed matrix, In the polarization transmission characteristics, polarization mode dispersion can be calculated as: in, and yes The characteristic value of .

6. The frequency-shift interferometry optical vector analysis device according to claim 1, characterized in that: The center frequency of the first unilateral digital bandpass filter (6021) is , the bandwidth is ΔΩ1; the center frequency of the second unilateral digital bandpass filter (6022) is , the bandwidth is ΔΩ1.

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